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So my bike was running rich, it had a wet plug with oil and gas, it would load up really bad idling so I bumped my pilot jet down 2 sizes from a 30 to a 25 which is perfect. I Left my main at 400 and did a full throttle run and checked the plug and it was blue/white so I put a 420 main in and it looked pretty much the same after another WOT test. I am running 40:1 and when I put my new pilot jet in I let the bike idle for about 2 minutes and pulled the plug and it looked perfect. So I'm pretty sure the pilot circuit is perfect. Is it possible I would have to go larger on my main? I tried moving my needle clip position to one below the middle position and it sputtered and ran horrible in the 1/4 to 3/4 throttle range so i moved it back to the clip above the middle where it was. I live at around 2400 feet. this is confusing. Plus now my bike has slight spooge, not too bad but its noticeable. I really just dont want to cause any serious damage by running my bike too lean. helpppp meeeeee

Edited by user:4

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The pilot circuit does not stop after you twist the throttle. Wheres the A/F screw set to?

You should get the main jet set before setting the pilot jet.

Go back to the 30p and needle clip in the middle see how it looks.

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youre not doing a proper plug chop for the main.

you need a new plug, 1 or 2 wot runs with no idleing (just start and take off wot), pull the plug, cut it, and check the mixture ring.

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Maybe put the 27.5 pilot with a 410-420 main and do a correct plug test. This is the exact reason why I swapped for the pwk and actually never ran the tmx carb. I find it hard to do a wot run unless Im in the desert. So its now really tuff to dial it in, damn city livin!

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this is one of my plugs ran with 2 WOT runs. brand new plug.

IMAG0067.jpg

Is that normal? Mine looked pretty similar to that. I thought it was supposed to be like mocah/tan colored. Anyways if that is right then I am good to go. I put my 27.5 pilot in today and a 390 main and air screw is 1 1/4 out and it seems to be really good right now. Still some spooge though :thumbsup:

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Is that normal? Mine looked pretty similar to that. I thought it was supposed to be like mocah/tan colored. Anyways if that is right then I am good to go. I put my 27.5 pilot in today and a 390 main and air screw is 1 1/4 out and it seems to be really good right now. Still some spooge though :thumbsup:

its normal if you did a proper plug chop. if your plug looks like that after a days worth of riding then you have a problem.

that plug has probably 10 seconds of run time on it and then it was removed. used plug installed and I rode back to the truck to drop it off.

all you are looking at here is the mixture ring which will form quickly at wot. the plug insulator will change color to a mocha color if I actually used it to ride the bike to my testing ground but then a plug chop is worthless because the whole plug is colored up.

warm up on used plug, change jets, install new plug, wot run, rinse and repeat with new main jet and new plug, cut the plug down and look at the ring.

you are pretty close with jetting to my friend however I can pretty much guarantee if your needle is in the stock position you are way rich. friend runs 27.5p, needle in 1st, 390-400m. weather dependent of course and sea level.

the needle position was the biggest change in response on his stock 01.

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i wish this was simple.

it is simple. you can cut plugs and do chops and all that other stuff but i dont personally do all those hoky poky things. if you listen to the engine and use some common sense it will make sense pretty fast. sounds like your whole carb is fairly close, just needs some fine tuning.

too big pilot typically wont idle. does yours idle ? if so then your in the ballpark. too small pilot and the revs hang and low rpm is erratic.

as for the needle, move the clip around and see what happens.

if your topend is blubbering and dont rev out clean or takes a few seconds to clean out then obviously you know the main is too big. not rocket science just common sense. drop it down 1 size at a time until you get the desired results you want.

tuning meens you may have to turn a few screws, change a few jets, play with the needle etc etc. make one change at a time and dont over complicate things. alot of folks make it hard and chase their tail in circles.

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its normal if you did a proper plug chop. if your plug looks like that after a days worth of riding then you have a problem.

that plug has probably 10 seconds of run time on it and then it was removed. used plug installed and I rode back to the truck to drop it off.

all you are looking at here is the mixture ring which will form quickly at wot. the plug insulator will change color to a mocha color if I actually used it to ride the bike to my testing ground but then a plug chop is worthless because the whole plug is colored up.

warm up on used plug, change jets, install new plug, wot run, rinse and repeat with new main jet and new plug, cut the plug down and look at the ring.

you are pretty close with jetting to my friend however I can pretty much guarantee if your needle is in the stock position you are way rich. friend runs 27.5p, needle in 1st, 390-400m. weather dependent of course and sea level.

the needle position was the biggest change in response on his stock 01.

the clip on my stock needle is one slot above the middle. making it one slot leaner. so you guys are at sea level, im at 2400 feet and i know you jet leaner for higher altitude so that being said, if anything im just a hair rich which is okay with me... right?

oh and by the way, what kind of oil and oil ratio are your friend running?

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it is simple.

i knew somebody would say that lol

and my bike idles great, the only thing i dont really like about it is that it takes a second to get on the pipe. im just not used to it, im used to lugging 4-strokes. another big thing about it is i just need to get used to riding my new bike! i compare it to other stuff that i shouldnt :thumbsup:

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the clip on my stock needle is one slot above the middle. making it one slot leaner. so you guys are at sea level, im at 2400 feet and i know you jet leaner for higher altitude so that being said, if anything im just a hair rich which is okay with me... right?

oh and by the way, what kind of oil and oil ratio are your friend running?

we used to run honda hp2 at 32:1, but we have been running yamalube 2r exclusively now, for the longest time. mostly due to the fact that we get twice as much product for about the same price. my last top end, shows no blowby with 53 hours on it, i see no reason to spend more for the hp2. we never stray from 32:1.

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we used to run honda hp2 at 32:1, but we have been running yamalube 2r exclusively now, for the longest time. mostly due to the fact that we get twice as much product for about the same price. my last top end, shows no blowby with 53 hours on it, i see no reason to spend more for the hp2. we never stray from 32:1.

awesome. do you think for someone like me that doesnt ride super hard, 32:1 would make me foul plugs? i just want to do as little damage to my engine as possible.

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awesome. do you think for someone like me that doesnt ride super hard, 32:1 would make me foul plugs? i just want to do as little damage to my engine as possible.

i have never fouled a plug, ever, and im not the fastest guy out there. still relatively new to the sport, but getting faster over the years every time we head out. we can lug these things around pretty good staying close to, but not on the pipe, for long periods of time depending on the terrain before we reach areas that allow for going WOT. i keep a backpack with me with 2 spark plugs and a wrench (one for each of our bikes), yet it has never seen the light of day for as long as ive had the bike. hell i was burning trans fluid for a bit due to a badly machines crank, and still didnt foul a plug.

your oil ratio is not going to foul your plug, your jetting will.

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i have never fouled a plug, ever, and im not the fastest guy out there. still relatively new to the sport, but getting faster over the years every time we head out. we can lug these things around pretty good staying close to, but not on the pipe, for long periods of time depending on the terrain before we reach areas that allow for going WOT. i keep a backpack with me with 2 spark plugs and a wrench (one for each of our bikes), yet it has never seen the light of day for as long as ive had the bike. hell i was burning trans fluid for a bit due to a badly machines crank, and still didnt foul a plug.

your oil ratio is not going to foul your plug, your jetting will.

Sounds like we have a similar riding style. I'm defiantly newer to the sport and I surly am not "fast" by most peoples standard.

Thanks for all the help! :thumbsup:

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You may have an air leak. Have you checked the crank seals or pressure tested the engine?

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